High Risk →

browser_hover

Hover over element on page

How to control browser_hover ↓

What browser_hover does on Better Playwright MCP

AI agents invoke browser_hover to trigger actions in Better Playwright MCP. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

High Risk

Why browser_hover needs a policy

Hovering is a browser action that triggers external operations (mouseover events, JavaScript handlers, UI state changes). It has no direct data modification or deletion, but it executes a real browser interaction that can cause side effects like revealing hidden menus or triggering scripts.

From the tool's definition 'Hover over element on page' — triggers a browser interaction (mouse hover) on a live browser session

Documented attack patterns abuse exactly the kind of access browser_hover gives an agent:

How to control browser_hover

PolicyLayer is an MCP gateway — it sits between your AI agents and Better Playwright MCP, and nothing reaches the server without passing your rules. This is the rule we recommend for browser_hover:

policy.json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "browser_hover": {
      "limits": [
        {
          "counter": "browser_hover_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

browser_hover stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

  1. Create a free account and register Better Playwright MCP — nothing to install.
  2. Add this policy — paste it, or build it visually.
  3. Point your MCP client (Claude, Cursor, anything) at your gateway URL.
RATE-LIMIT THIS TOOL →

Free to start. No card required.

Related tools and policies

Go deeper

Questions about browser_hover

What does the browser_hover tool do? +

Hover over element on page. It is categorised as a Execute tool in the Better Playwright MCP MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on browser_hover? +

Register the Better Playwright MCP server in PolicyLayer and add a rule for browser_hover: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Better Playwright MCP. Nothing to install.

What risk level is browser_hover? +

browser_hover is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit browser_hover? +

Yes. Add a rate_limit block to the browser_hover rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block browser_hover completely? +

Set action: deny in the PolicyLayer policy for browser_hover. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides browser_hover? +

browser_hover is provided by the Better Playwright MCP server (livoras/better-playwright-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Better Playwright MCP tool call.

Start from Better Playwright MCP, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

Free to start. No card required.

29 Better Playwright MCP tools catalogued and risk-classified — across an index of 43,000+ MCP servers.

// GET IN TOUCH

Have a question or want to learn more? Send us a message.

Message sent.

We'll get back to you soon.